Process for preparing a polymer dispersion and a polymer dispersion
a technology which is applied in the field of polymer dispersions and polymer dispersions, can solve the problems of time-consuming cleaning procedures of reaction equipment, increased active content above a certain level, and low process viscosity, and achieve high-stable polymer dispersions. , the effect of low process viscosity
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Benefits of technology
Problems solved by technology
Method used
Examples
example 1
[0041]A stabiliser made of methacrylic acid (MAA) and 2-acrylamido-2-methyl-1-propane sulphonic acid (AMPS) in a mole ratio of 80:20 was prepared: A mixture of 85 g ultra-pure water, 8.24 g AMPS (solid), 16.62 g MAA and 11.5 g NaOH (50%) was adjusted to pH 7 by means of NaOH (50%). 0.02 g EDTA (solid) was given into the mixture. Further ultra-pure water was added to reach a total mass of 127 g. This was filled into a double-wall 150 ml glass reactor with anchor stirrer, nitrogen inlet, reflux condenser and bottom valve. The mixture was stirred with 150 / min and purged with nitrogen. The reactor content was heated up to 45° C. 0.05 g V-50 (2,2′-Azobis-(2-amidinopropane) dihydrochloride) were added. After 60 min, temperature was increased up to 50° C. The mixture was polymerised over 72 h at 50° C. and 150 / min. The stabiliser was purified and isolated by ultrafiltration and freeze-drying. The weight average molecular weight was about 15.000 g / mole.
examples 2-7
[0042]A polymer dispersion was prepared by polymerising a monomer mixture comprising acrylamide and acrylic acid in the presence of a polymeric stabiliser and a polymeric co-stabiliser.
[0043]A mixture of 30 g water, 24.3 g co-stabiliser polyacrylic acid (45%, Sigma-Aldrich, Mw 1,200), 1.2 g stabiliser poly (MAA-co-AMPS) (80:20) copolymer (according to example 1, Mw 15,000), 28.1 g acrylamide (50 wt %), 1.07 g acrylic acid, 0.04 g sodium formiate, 0.03 g EDTA, and 1.17 g NaOH (50 wt %) was stirred and the pH was adjusted to 7. Water was added up to 100 g and during 8 hours azo-initiator VA-044 (4%) (2,2′-azobis-(N,N′-dimethyleneisobutyramidine) dihydrochloride, Wako) was added (0.5 g in steps). The temperature was kept at 35° C. After 16 hours, the stirring was stopped.
[0044]Five further polymer dispersions were prepared using the same procedure as described above but changing the ratio non-ionic monomer and anionic monomer, using a second non-ionic monomer in the dispersed polymer, ...
example 8
[0055]The polymer dispersions prepared in Examples 2-4 were tested for retention and dewatering performance in papermaking processes by means of a Dynamic Drainage Analyser (DDA) available from Akribi, Sweden. The furnish used was based on 60% by weight of bleached 80 / 20 birch-pine pulp and 40% by weight of calcium carbonate. The stock volume was 800 ml, the pulp concentration 5 g / L and the conductivity 1.5 mS / cm. The stock was stirred at a speed of 1500 rpm while the following was added to the stock: an anionic trash catcher (0.5 kg / t), polymer dispersion (1.0 kg / t) and finally anionic inorganic particles (0.5 kg / t). The temperature was 22.5° C. A vacuum of 0.35 bar was used for the analysis. The retention time (s) and turbidity (NTU) was measured.
[0056]
TABLE 2Polymer dispersions and application testsApplication testsPolymerPolymer loadRetention timeTurbiditydispersion(kg / t)(s)(NTU)Example 21.015.2198Example 31.014.6220Example 41.013.2214
[0057]It is concluded that the dispersions a...
PUM
| Property | Measurement | Unit |
|---|---|---|
| weight % | aaaaa | aaaaa |
| weight % | aaaaa | aaaaa |
| mol % | aaaaa | aaaaa |
Abstract
Description
Claims
Application Information
Login to View More